The Rt values are above 1 in all regions. The plots of the Rt over time show a plateauing in most regions in the most recent weeks, with decreases in the North East and Yorkshire and the North West. However, as Rt is remaining above 1, the number of new infections continues to rise, although at a slower rate in some regions. These lower values of Rt might be the result of various social distancing interventions, but the impact is not strong enough to reduce the Rt values below 1. The rise in the number of new infections will continue unless additional and more effective interventions are introduced. We will monitor our estimates as the measures announced on Saturday 31st October are put in place.
Real-time tracking of an epidemic, as data accumulate over time, is an essential component of a public health response to a new outbreak. A team of statistical modellers at the MRC Biostatistics Unit (BSU), University of Cambridge, are working to provide regular now-casts and forecasts of COVID-19 infections and deaths. This information feeds directly to the SAGE sub-group, Scientific Pandemic Influenza sub-group on Modelling (SPI-M), and to regional Public Health England (PHE) teams.
We fit a transmission model (Birrell et al. 2020) to a number of data sources (see ‘Data Sources’), to reconstruct the number of new COVID-19 infections over time in different age groups and NHS regions, estimate a measure of ongoing transmission and predict the number of new COVID-19 deaths.
We use:
Data are stratified into eight age groups: <1, 1-4, 5-14, 15-24, 25-44, 45-64, 65-74, 75+, and the NHS England regions (North East and Yorkshire, North West, Midlands, East of England, London, South East, South West).
Value of \(R_t\), the average number of secondary infections due to a typical infection today.
The percentage of a given group that has been infected.
NB: negative growth rates are rates of decline. Values are daily changes.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | 0.05 | 0.03 | 0.06 |
| East of England | 0.06 | 0.02 | 0.10 |
| London | 0.04 | 0.00 | 0.07 |
| Midlands | 0.06 | 0.03 | 0.08 |
| North East and Yorkshire | 0.02 | 0.00 | 0.05 |
| North West | 0.01 | -0.01 | 0.03 |
| South East | 0.06 | 0.02 | 0.10 |
| South West | 0.08 | 0.04 | 0.12 |
Halving times in days, if a region shows growth than value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | NA | NA | NA |
| East of England | NA | NA | NA |
| London | NA | 589.61 | NA |
| Midlands | NA | NA | NA |
| North East and Yorkshire | NA | NA | NA |
| North West | NA | 75.97 | NA |
| South East | NA | NA | NA |
| South West | NA | NA | NA |
Doubling times in days, if a region shows decline then the value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | 15.03 | 11.46 | 21.21 |
| East of England | 11.33 | 7.26 | 31.07 |
| London | 17.67 | 9.54 | NA |
| Midlands | 11.48 | 8.28 | 21.16 |
| North East and Yorkshire | 28.63 | 14.97 | 4201.76 |
| North West | 50.36 | 20.70 | NA |
| South East | 11.39 | 7.11 | 37.19 |
| South West | 8.36 | 5.58 | 17.76 |
NB: negative growth rates are rates of decline. Values are daily changes.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | 0.05 | 0.04 | 0.06 |
| East of England | 0.06 | 0.03 | 0.10 |
| London | 0.04 | 0.01 | 0.08 |
| Midlands | 0.07 | 0.04 | 0.09 |
| North East and Yorkshire | 0.03 | 0.01 | 0.06 |
| North West | 0.03 | 0.01 | 0.05 |
| South East | 0.06 | 0.02 | 0.10 |
| South West | 0.08 | 0.04 | 0.13 |
Halving times in days, if a region shows growth than value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | NA | NA | NA |
| East of England | NA | NA | NA |
| London | NA | NA | NA |
| Midlands | NA | NA | NA |
| North East and Yorkshire | NA | NA | NA |
| North West | NA | NA | NA |
| South East | NA | NA | NA |
| South West | NA | NA | NA |
Doubling times in days, if a region shows decline then the value will be NA.
| Region | Median | 95% CrI (lower) | 95% CrI (upper) |
|---|---|---|---|
| England | 14.65 | 11.91 | 19.24 |
| East of England | 10.83 | 6.94 | 25.16 |
| London | 16.11 | 8.80 | 107.51 |
| Midlands | 10.47 | 7.54 | 17.85 |
| North East and Yorkshire | 20.73 | 12.53 | 56.03 |
| North West | 23.90 | 14.16 | 81.61 |
| South East | 11.28 | 7.02 | 30.64 |
| South West | 8.24 | 5.46 | 16.63 |
The blue lines is show when interventions have been introduced (lockdown on 23 Mar and the relaxation of measures on 11 May), and the red line shows the date these results were produced (30 Oct).
The figure below shows the probability that \(R_t\) is greater than 1 (ie: the number of infections is growing) in each region over time. Clicking the regions in the legend allows lines to be added or removed from the figure.
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